1. Field of the Invention
This invention relates to a stamper holding apparatus for use in an injection mold, especially, of the type having a stamper disposed on the mirror surface of one of the stationary and movable mirror blocks.
2. Description of the Prior Art
Conventionally, in this type of injection mold, a stamper standing for a master of compact disk etc. is supported, at its outer circumferential edge portion, by a holding member so as to be held between the mirror surface and the holding member. More specifically, the holding member is clamped to either a stationary plate or a movable plate by means of fixing bolts and the fixing bolts are tightened to urge the holding member to hold the stamper.
In the conventional holding apparatus as above, the holding member is removed from the stationary or movable plate when exchanging the stamper, and during this procedure, the fixing bolts have to be mounted or dismounted with the mold open. Obviously, this work is time-consuming. In addition, since the mold is kept open for a long time, the amount of dust deposited on the stamper and the mirror surfaces increases. Moreover, a tool, such as a wrench, is needed for carrying out the work and the mirror surface may accidentally be damaged by the wrench.